136 PALAEONTOLOGY OF CALIFORNIA. 



Figure, natural size. 



Locality : Tuscan Springs, Tehama County (Division A.), collection of the Cali- 

 fornia Academy of Natural Sciences. 



This shell approaches in shape T. Leonensis, Con. ; but the ribs are plain, without 

 an intermediate line, and with the interspaces deeper. The distance of the upper 

 rib from the top of the whorl is also a strong distinguishing character. 



GALERUS, Humph. 



G. EXCENTRICUS, n. S. 

 PI. 20, Fig. 95, and PI. 29, Fig. 232 a. 



Shell rounded, irregular; spire low, excentric; volutions two 

 to two and a half. Body whorl irregularly rounded, sometimes 

 slightly flattened above. Suture obliterated. Surface marked 

 by very oblique stria? of growth. 



Figures, natural size. 



Localities: Northeast of Martinez; Clayton, above and below the coal; in an 

 isolated mass of Cretaceous rocks, seven miles south of Martinez ; also at San 

 Diego ; not rare near Fort Tejon (Division B.). 



CRYPTA, Humph. 



■ 



Crepidula, Lam. 

 Subgen. SPIROCRYPTA, Gabb. 



Shell oval, convex above, concave below, summit posterior, 

 lateral and submarginal, spiral. Internal plate attached to the 

 margin on the lower or outer side, curving upwards and inwards, 

 and uniting with the opposite side at a considerable distance from 

 the margin. 



This form approaches the subgenus Crepipatella of Lesson, but 

 differs in the more mairkedly spiral character of the apex, and in 

 the very oblique position of the internal plate. This plate pre- 

 sents a subspiral character, forming the strongest link yet dis- 



